Homobinuclear Ru-Ru and heterobinuclear Ru-Rh complexes with alkynyl and vinylidene ligands as molecular units

The chelate complex [RuCl2{κ2(P,O)-i-Pr2PCH2CH2OMe}2] (1) reacted, in the presence of CF3SO3Ag, with 1 equiv of C6H4(CºCH)2-p (4) to afford the mononuclear vinylidene compound [RuCl(C=CHC6H4-p-CºCH){κ2(P,O)-i-Pr2PCH2CH2OMe}2](CF3SO3) (3). From 1 and 0.5 equiv of 4, the binuclear bis(vinylidene) complex [RuCl{κ2(P,O)-i-Pr2PCH2CH2OMe}2(C=CHC6H4-p-CH=C)RuCl{κ2(P,O)-i-Pr2PCH2CH2OMe}2](CF3SO3)2 (6) was obtained. The related compound [RuCl{κ2(P,O)-i-Pr2PCH2CH2OMe}2(C=CHC6H4-m-CH=C)RuCl{κ2(P,O)-i-Pr2PCH2CH2OMe}2](CF3SO3)2 (7) was prepared from 1, 0.5 equiv of C6H4(CºCH)2-m (5), and silver triflate. The reaction of 2 or 3 with [RhCl(P-i-Pr3)2]2 (8) in the molar ratio of 2:1 yields, by addition of the 14-electron fragment [RhCl(P-i-Pr3)2] to the uncoordinated C—C triple bond, the heterobinuclear complexes [RuCl{κ2(P,O)-i-Pr2PCH2CH2OMe}2(C=CHC6H4-m/p-CºCH)RhCl(P-i-Pr3)2](CF3SO3) (9, 10) which slowly rearrange at room temperature to give the bis(vinylidene) isomers [RuCl{κ2(P,O)-i-Pr2PCH2CH2OMe}2(C=CHC6H4-m/p-CH=C)RhCl(P-i-Pr3)2](CF3SO3) (11, 12).Key words: ruthenium, rhodium, vinylidene complexes, alkyne complexes, phosphine complexes.